The subject matter disclosed within generally relates to industrial control systems, and more particularly to systems and methods that provide cooling mechanisms for power components associated with industrial control systems.
Industrial control systems, by their nature, are located in a variety of environments. Some of these environments can have a variety of air-born contaminates that can be damaging to electrical components. Alternatively, certain environments may require regular cleaning with water and/or other chemicals which can also damage sensitive electrical and power components. Further, some environments may require pressure washing, requiring electrical enclosures to prevent liquids from contacting the electrical components, causing damage or dangerous situations. Thus, installation of industrial control systems in environments containing potential contaminates can require specialized installation systems to protect the electrical components.
When industrial control systems are installed in environments where they are required to be isolated from potential contaminates, the electrical components are often placed in an enclosure. These enclosures, depending on the level of sealing necessary, can be designed to prevent the ingress of liquids, or, in certain situations, from the outside air in general. As these sealed enclosures are generally more expensive than standard electrical enclosures, they are often sized to accommodate multiple components such that the number of enclosures needed can be reduced. This often results in long cabling and conduit runs to and from various equipment and processes; thereby increasing both cost and complexity to a system.
Additionally, the sealed nature of these enclosures required them to, generally, be larger than non-sealed enclosures in order to accommodate the heat generated by the internal electrical components. As the enclosures can be required to be sealed from the outside air, efficient cooling of the internal electrical components is difficult and often requires significant oversizing of the enclosure to ensure that the heat can be adequately dissipated. This additional size further increases material cost of the enclosures and requires more of the industrial environment real estate be allocated for these enclosures. This inefficient use of space can have a significant impact on the efficiency and utilization of the industrial environment in addition to requiring additional capital for the materials and installation.
Passive heat dissipation devices such as heat sinks can be used to dissipate heat produced by the components. Additionally, heat sinks can be used in conjunction with an active cooling device such as a stirring fan, or, where feasible, used in lieu of an active cooling device. Heat sinks require additional space in the enclosure and sufficient air volume to effectively dissipate the generated heat. Further, heat sinks can be difficult to apply to certain power components due to their geometrical features. A prime example are power capacitors, such as those used as bus capacitors for variable frequency drives. These devices are often cylindrical and, in some instances, fragile. Attempts at removing heat from power capacitors with a heat sink can be difficult as heat sinks rely on a thermally efficient coupling to the device to properly dissipate heat from the component. Thermally efficient coupling is generally accomplished by placing as much of the component as possible in contact with the heat sink with a tight physical connection to ensure heat can easily transfer from the component to the heat sink.
Generally, components are connected to a heat sink on a substantially flat portion of the component to allow for the greatest surface area to be in contact with the heat sink. These substantially flat surfaces are also generally the strongest portions of the components, allowing for a strong coupling between the component and the heat sink. However, capacitors, and particularly power capacitors, are generally cylindrical in shape, thereby making it difficult to couple a heat sink to the capacitor. Further, cylindrical capacitors can be easily deformed with little force. Deformation of the power capacitors can affect the properties of the capacitor adversely, even causing failures, which can result in unplanned downtime to repair. This is made more complicated by the non-uniformity of many power capacitors, making it difficult to produce a heat sink that can couple to the power capacitor to allow for efficient cooling while preventing any physical deformation or damage to the power capacitor.
Thus, it would be advantageous to have devices and methods that allows for a heat sink to be safely and efficiently coupled to a power component, such as a capacitor, to efficiently cool the power component while reducing the likelihood of physical damage to the power component.